at90ls4433 ATMEL Corporation, at90ls4433 Datasheet - Page 80

• Manufacturer Part Number: at90ls4433
• Description: At90s4433 8-bit Avr Microcontroller With 4k Bytes Of In-system Programmable Flash
• Manufacturer: ATMEL Corporation

Port D
Port D Data Register – PORTD
Port D Data Direction Register
– DDRD
Port D Input Pins Address –
PIND
80
AT90S/LS4433
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors.
Three I/O memory address locations are allocated for Port D, one each for the Data
Register – PORTD, $12($32), Data Direction Register – DDRD, $11($31), and the Port
D Input Pins – PIND, $10($30). The Port D Input Pins address is read only, while the
Data Register and the Data Direction Register are read/write.
The Port D output buffers can sink 20 mA. As inputs, Port D pins that are externally
pulled low will source current if the pull-up resistors are activated.
Some Port D pins have alternate functions as shown in Table 26.
Table 26. Port D Pin Alternate Functions
The Port D Input Pins address (PIND) is not a register; this address enables access to
the physical value on each Port D pin. When reading PORTD, the Port D Data Latch is
read, and when reading PIND, the logical values present on the pins are read.
Bit
$12 ($32)
Read/Write
Initial Value
Bit
$11 ($31)
Read/Write
Initial Value
Bit
$10 ($30)
Read/Write
Initial Value
Port Pin
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
PORTD7
PIND7
DDD7
R/W
R/W
N/A
R
7
0
7
0
7
Alternate Function
RXD (UART Input Line)
TXD (UART Output Line)
INT0 (External Interrupt 0 Input)
INT1 (External Interrupt 1 Input)
T0 (Timer/Counter 0 External Counter Input)
T1 (Timer/Counter 1 External Counter Input)
AIN0 (Analog Comparator Positive Input)
AIN1 (Analog Comparator Negative Input)
PORTD6
PIND6
DDD6
R/W
R/W
N/A
R
6
0
6
0
6
PORTD5
PIND5
DDD5
R/W
R/W
N/A
R
5
0
5
0
5
PORTD4
PIND4
DDD4
R/W
R/W
N/A
R
4
0
4
0
4
PORTD3
PIND3
DDD3
R/W
R/W
N/A
R
3
0
3
0
3
PORTD2
PIND2
DDD2
R/W
R/W
N/A
R
2
0
2
0
2
PORTD1
PIND1
DDD1
R/W
R/W
N/A
R
1
0
1
0
1
PORTD0
PIND0
DDD0
R/W
R/W
N/A
1042H–AVR–04/03
0
0
0
0
0
R
PORTD
DDRD
PIND